Spinner was not spining - should use SetValue, not SetValues.
Also fixed sln - VS2019 not want to open sln by double click in explorer - added empty line.
Also fixed sample project - VS2019 not showing all sources.
* Update to .NET 6
I update not only samples, but also codegen tools, because .NET 5 is not LTS and in 4 month would be out
Closes#306
* Add .NET 6.0 support to actual templates
* Dont forget about FSharp and VB.NET
* Revert choice option in parameters